Mark Zuckerberg married his girlfriend, Priscilla Chan in a surprise ceremony at his Palo Alto, Calif., home before 100 guests – and the Winklevoss twins.

Mark Zuckerberg married his girlfriend, Priscilla Chan in a surprise ceremony at his Palo Alto, Calif., home before 100 guests and the Winklevoss twins.

The tech mogul memorialized the momentous event in the most fitting way for the Facebook generation, by posting an update to his page that said: “Mark added a life event to May 19, 2012 on his timeline: Married Priscilla Chan.”

According to the Associated Press, Zuckerberg’s marriage to Priscilla Chan took place in front of about 100 invited guests who thought they were celebrating Ms. Chan’s medical school graduation. It all happened in Zuckerberg’s backyard.

The couple met while both were attending Harvard, and have been together for nine years.

Zuckerberg, 28, even took off his infamous hoodie for the wedding in favor of a dark blue suit and tie. The bride wore a white, body-fitting lace gown.

The Winklevoss Twins, who have sued Zuckerberg twice for “stealing” their idea for Facebook – served as “best men” for the ceremony. In their speech, the twins said that they were first ones to see Priscilla and believe that Zuckerberg stole her from them.

“It was our idea to date Priscilla. We introduced her to Mark and he stole her away,” said a Winklevoss. “We are going to sue to get full custody of her.”

The couple, who met at Harvard and have dated for nine years, deflected media attention by telling their guests they’d been invited to his home to celebrate Chan’s recent graduation from medical school — but then surprised the crowd by getting married instead. They had been planning the wedding for four months, People reported.

While he could afford to give her a diamond the size of an SUV, the Facebook billionaire gave Chan “a very simple ruby” that he designed himself, according to a guest authorized to speak for the couple.

Guests dined on food from the couple’s favorite restaurants, Palo Alto Sol and Fuki Sushi They had a desert of mouse-shaped chocolates that the pair ate on their first date nine years ago, according to People.

Chan, 27, graduated from the University of California, San Francisco on Monday, the same day Zuckerberg turned 28.

She plans to be a pediatrician.

Zuckerberg is Facebook’s single largest shareholder and controls the company with 56 percent of its voting stock. He is ranked 14th on Forbes’ list of richest Americans.

Zuckerberg grew up about 10 miles north of New York City in Dobbs Ferry .

Within hours of announcing his marriage, more than 220,000 people had “liked” the news on Facebook .